Sahih Muslim 6754
صحيح مسلم#6754SahihAbu Huraira reported Allah's Apostle (ﷺ) as saying:Verily Allah has fixed the very portion of adultery which a man will indulge in, and which he of necessity must commit. The adultery of the eye is the lustful look, and the adultery of the tongue is the licentious speech, the heart desires and yearns, which the parts may or may not put into effect
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Every narration in Sahih Muslim is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 46:32